Internal mandrel for sectional boiler headers



Aug. 9,1927

J. H. HINMAN INIBRNAL MANDREL FOR SECTIONAL BOILER HEADERS 2 Sheets-She et l Filed Nov. 11, 1925 Patented Aug. 9,

JOHN H. mum-An; or S'IeLOUISQ MISSOURI, AssI NoR 'ro HEINE'BoiLEE-oOMPANY', a

. I QFST. LU,I$; Mxsso'uBLA QEPOBATIQN oFjMIssoURIE a jinrEnNAr-g immanenroe SECTION-AL BOILER HEADERS.

i Application filed Nov ber 1 1, 1 925 Serial No. 138,376.

I [This invention relates'to an internal man- 'drel that is adapted to be arranged inside of Va metal tube 'which is being; deformed to produce a sectional boiler header'ror tube 5 header of the kind described in the-United States patent of AlfredCotton for method and apparatus for making-sectional headers,

No. 1,565,061, dated December 8, 1925;

The mainobject of my invention is to produce a mandrel forthe purpose described which is of such design that it can be 1nanu-' factured easilyby simple machine operations at alowcost.

Another object is; to provide a mandrel of the type that comprises die bars and acollapsible supporting unit for the die bars which is equipped withlan-efiicient ineans'for partially collapsing the die bar supporting unit at thecompletion of the deforming operation before theheader-has had aphance to seize or grip the die'elementadue to cool-- ing and shrinking of the header;

-And still another ob ect is to provide a mandrel of the type just referred to which is so constructed that after it has been 'parti ally collapsed, the mandrel and the header can be removed as a single unit fromthe press by exerting an upward pull on the mandrel said Cotton patent, that is produced by ar-H Other objects and desirable features of my" invention will be hereinafter pointed out. '1

Figure l of the drawings is a perspective view of a Cottonboilerheader.

Figure 2 is a longitudinal sectional view of a mandrel constructed in accordance'with.

my invention, showingthe mandrel expanded and arranged in operative position inside of the header.

FigureB is a similar view showing} the mandrel partly collapsed. v Figure 4 is a longitudinal sectional view, showing the collapsible supporting means for the die bars removed, preparatory to withdrawing the die bars from the header. Figure 5 is a. horizontal sectional view, taken on the line 55'of Figure 2. a

Figure 6 is a horizontal sectional View, taken on the line 6-6 of Figure 2; and

Figure 7 is a longitudinal sectional view,

illustrating a modification of my invention.

In the drawings 00 designates a sectional boiler header of the kind described in the ranging a circular or oval metal tube between two sidedies and a front and rear die,

and then-moving saiddies inwardly towardsthe longitudinal axis of the tube seas to def i formthe tubein such a-Waya's to produce-a headerhaving corrugated lateral sides and frontand rear sides that have flat seatfaces I 1 1, disposed at an angle to theplongitudinal axis of the header, which "flat seat faces are adapted to have hand holesand tube holes formed in same.

subject-matter of this ,applicationif Said mandrel is composedof two same, and a collapsible supporting means arranged between said die bars-forholding them in rigidrelation during the deform? mg operat1on,' sald supportmglmeans consistmg of a unit capable of being wlthdrawn v bodily from operativeposition between. the j i die bars and constructed so that it can be partially collapse-d at the completion of the deforming die bars to move inwardly suflicientlyfto- Operation, h y;permitting the .80

wards the longitudinal axisxofeofthe man-R drel'to, prevent the' die elements 2 from be} ing gripped by the header as it shrinks, 1 V I The 1e supporting unit just referred to-1s preferably composedof two wedges B other and interposed between the die bars A,

as shown inFigure 2.. During the deformasv f andBV-Qof approximately the length of the v mandrel, arranged in engagement with eaoh held against "longitudinal movement in either direction andtheyare combined with the die bars in such a waythat said parts co-o-perate' with each-'other'to produce a rigid supporting means for the portions of the tube that areb'eing deformed to produce the flat seatlfacel of the header. In the form of my invention herein illustrated the wedges Band B'are held infixed rela.- tion witheach other and alsoin v fixedrela tion with the die bars during the deforming operation, by means of a .pin C-that is arranged transversely through aligned holes in the upper-end portions of the die barsland in the upper. end portions of the wedges B and B said pin "being'adapted to be insert ed transversely through said parts before the mandrel is positioned inside of the tube that isf-tobe deformed. I also; prefer to, i i no equip the mandrel with a means for clamp;

2o :fmedia'tely after 'thercompletion of the deing the lower end portions of the die bars andv the wedges B and .13! togetherfthe means herein illustrated for this purpose consisting of a sleeve D at the lower end of the mandrel which surrounds said diebars land wedges and provided with guide pin f 3 that enters ahplefiiin one of the d i'e bars, I

and a clamping screw4 arranged opposite said guide pin that bearsagainstthe outside Figure 6.

face. of the other die .bar, as sh'ownfin Due tothe factthat the wedges B'- l I have a relatively slighttaper, considerable force or 'pressure'is required to displace said wedges o'rmove one wedge longitudinally relatively to the other, so as to partiallycollapse the anandrel at the completion of a the deforming operation. It:is also-necessary that the die'ibarsupporting unit formed by-ft-he' wedgesB and B" be collapsed 'im forming operation in order toprevent-the thati-thefdie elements of the z'mandrel will i "be seized by the header-J Till 8 11163118 "above referred to canfbeconstructed in various ways without'departingifrom the spirit of my invention but I have herein illustrated I "it as consisting of a lever E at the'upper end of the mandrel arranged so that it can" be engaged and moved-upwardly by the hook 5 of aihois'ti'ng apparatus and combinedwith the wedges; B and B in such amanner that when it isactuated or rocked upwardly it exerts pressure-on at least one element 01": the

die bar supporting unit in a: direction to 5 partially collapsesaid ,unit or eauseithe Fwidthio'f same to be -red-uced sufliciently to permit; the die bars to -'move inwardly Sllghtly'tOWEL-IdS the longitudinal axis of the mandrel; One convenient way of combining the leyer E with the wedges B and B is to pivotally connect said lever to links .6,

'whicln'turn, are pivotally connected tothe wedge B by meansof vtrunnions or pins 7 on said wed-ge'that pro ect intowholes in said V linikgthe-leverE being pivotally connected to the upper ends of said links by across pin 8 and arrangedsothat a curved portion 9 at'the end of said lever normally bears against a curved surface 1O at-the extreme,

upper end "of the wedge B. 1

' During the operationi of arranging the mandrel inside 0f the tube, preparatory to i the deforming operation,"thevlever E and lin'ks6fserve as a means torconnecting the wedge B bears.

mandrel to a hoisting mechanism that is, used to lowerithe mandrel, into the press.

At the completion of the deforming opera-i tion the pinC. at the upper end of theman 'drel is withdrawn iromenga'gement with 7 {the die bars A and wed'gesjBand B" and the lever E is then rocked upwardly into the position shotiuiinbrokh lines in Figureg by pressure eXerted on the lever E by the hook5 of the hoisting mechanism. During,

this upward movement of the lever ET the curvedend p0rt1on9 of Stlld'lGVGI rocks on the curved bearing surface 10 atthe' upper endot' the wedge B,, and the link dexert an upward pull on the .1 wedg-e B, thereby starting the wedge B and causing it to break loosefrom the wedge B and. the die bar against which the outer face olf'said The upward movement of the hoistinglhook 5 is continued until-a hole 11. in the wedge B comes into alignmentiwith the holes in-the upper end portions of the die bars and the wedge B in which, the' pin G was ori inally positioned, andJthe'reafter the pin C is passedtransversely through said holes, as shown in Figure 8,ther eby" causing the wcdgesB and B to be securely locked together in their displaced position and also causingsaid wedges to be locked with the die bars. In View of thefact: that the die bars are now rigidly coupled with the die bar supporting' unit'of the mandrel,

which in turn, is coupled with thehoisting mechanism by means of the links 6 and leve-r- E, the hoisting mechanism can be used A" 'tofhtt the mandrel and the header as :a

single unit out of the press, the angular shape OftllQ die elements 2011 the mandrel and the fact thatthemandrel is onlyrpartially collapsed, insuring theheader movling upwardly out of the press with the manc rel. I

I A mandrel of the construction above described can be manufactured at a low cost i and by simple machine operations, owing to the fact that each of the wedges B and B has only a single taper, consisting of a continuous, straight surface, and another desir'ablecharacteristic of such a mandrel: is

that it is provided at its upper end withya means, to wit, t-he'lcver E and link 6- or equivalent device, that enables the mandrel to be partially collapsed before the header has hadan opportunity to shrink and grip the the elements 2 of the mandrel. "Still another desirable feature of such a mandrel is'that them-cans that is used to partially collapse the mandrel also constitutes a connectionbetween the mandrel and a hoisting mechanism that can be used to lower the mnndrel' nto the Press and withdraw the mandrel, together with the header, from the dies of the press. c a p In Fi 'u-re 7' of the drawings I have ill-usvtrated a mandrel that is similar to themandrel shown-in Figures 12 and .3, exce,pt that vided with die elements, a collapsible means the 'die barsupporting unit of themandrel p is formed by a pair of upper wedges G and G and a pair of lower wedges]? and F said wedges being approximately one-half the lengthof'the mandrel and arranged as shown in Figure 7. i V 1 Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A'mandrel for internally supporting a tube that is being deformed to produce a sectional header, consisting of die bars'profor rigidly supporting said die bars during the deforming operation comprising a pair' of members arranged between said the bars gripping the die elements;

2. A mandrel for internally supporting a tube that is being deformed to produce a sectional header, consisting of die bars provided with die elements, a collapsible means for rigidly supporting the die barsduring the deforming operation comprising apair of oppositely-inclined wedges providedwith aslight taper, one of said wedges being adapted to be moved longitudinally relatively to the other wedge at the'completion of the deforming operation for the purpose described, and means for enabling said I wedges to be connected with the die bars so that the mandrel and header can be withdrawn as a unit from the press a tube that is being deformed to produce a sectional header, consisting of die bars provided with die elements, a collapsible unit for rigidly supporting said die bars during the deforming operation comprising oppositely-movable members provided with co operating inclined surfaces, and a means for collapsing said unit that is also adapted to be used for connecting the mandrel to a hoisting mechanism.

4. A mandrel for internally supporting a tube that is b'eingdeformed to produce a sectional header, consisting of die bars provided with die elements, a collapsible unit for rigidly supporting said die bars during the deforming operation'comprising a plurality of relatively movable members, means for actuating said members to partially collapse the mandrel at the completion of the deforming operation, and means vifor enabling the die bars to be connected with said unit in its collapsed condition, whereby the mandrel and theheader can be withdrawnas a single unitfrom the'press.

5. -A mandrel for internally supporting adj tube that is being deformed to produce a sectional header, consistingof' die bars provided with die elements, a collapsible unit for rigidly supporting said die bars during the deforming operation comprising oppo-v sitely-movable members provided with co operating inclined surfaces, and a lever combined with said members and'adapted to tially collapse the mandrel;

6.'A mandrel for internally supporting a "be actuated to effect a change in the relav tive position of said members so as to parr bers equipped with oppositely-inclined surfaces that co-operate with eachother to vary the width of said unit when one of said members is moved longitudinally relatively to the other, and a lever "at'the upper end of the mandrel arranged to bear on one of said members and connected with the other 7 member so as to effect relative longitudinal movementiof said members when said lever is actuated. 1

7. A mandrel for internally supporting a tube that is being deformed to produce a sectional header, consisting of die'bars provided with die elements, a collapsible unit for rigidly'supporting the die bars during the deforming operation comprising a vpair oof oppositely-inclined Wedges interposed-be- I tween said die bars, a lever at theupper end 3. A mandrel for internally supporting I i of the mandrel arranged to bear on one of lever to the other wedge.

said wedges, and links for connecting said 7 8. A mandrel for internally supporting a tube thatis being deformed to produce a sectional header, consisting of die bars pro-,

vided "with die elements, a collapsible unit for rigidly supporting said die, bars'during the deforming operation composed of a pair.

of oppositely-inclined wedgesinterposed between saiddie bars, means at the lower-end of the mandrel for clamping said'wedges', together, a removable means at the upper operated at the completion of'the'deformmg operation to effect a change in the relative position of saidwedges so as to permit the die bars to move inwardly towards thev longitudinal axis of the mandrel.

' v JOHN H.

I-IINM AN, 

